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Chemistry

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The ionic product of water, Kw = 2.93 × 10−15 mol dm−6 at 10 °C. Calculate the pH of a 0.0131 mol dm−3 solution of calcium hydroxide at 10 °C Give your answer to two decimal places.

[OH-] = 0.0262 mol dm-3[H+] = (Kw/[OH-]) = 2.93 x 10−15 / 0.0262 (= 1.118 x 10−13) pH = (− log (1.118 x 10−13) = 12.9514 = 12.95

Answered by William B. • Chemistry tutor

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What are the special properties of graphite and diamond- why are they different.

both Graphite and diamond are giant covalent structures they both have have high melting points and are insoluble due to their complex structures

Answered by William B. • Chemistry tutor

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What is a radical?

A species with an unpaired electron, that is very reactive. For example, oxygen radicals involved in ozone depletion.

Answered by Emma S. • Chemistry tutor

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Why is the Mg2+ ion smaller in radius than the Na+ ion?

To answer this we need to compare the two ions. The main difference between the two ions is the number of protons in the nucleus - Magnesium has one more proton than Sodium, however, if you look at the el...

Answered by Jonathan H. • Chemistry tutor

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Describe, in three steps, how you would synthesise phenylethylamine (C6H5CH2CH2NH2) from methylbenzene, giving reagents and conditions for each step. For each step, state the type of reaction that occurs.

Methylbenzene (C₆H₅CH₃) can be reacted with chlorine in the presence of UV light. The type of reaction is free radical substitution, and this produces phenylchloromethane ...

Answered by James H. • Chemistry tutor

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